Question

Greg and Kevin both travel between two towns that are 90 miles apart. Greg travels and it takes him 1 hour 30 minutes. Kevin cycles and it takes him 7 hours 30 minutes. Work out the difference between the average speed.

Answer 1

48 miles/hour

Explanation:

The average speed is the ratio of the total distance traveled to the total time taven, it i given by the formula:

Average speed = total distance / total time

For Greg, the total distance = 90 miles and the total time = 1 hour 30 minutes = 1 hour + (30/60) hour = 1.5 hours. Hence:

Average speed = 90 / 1.5 = 60 miles/hour

For Kevin, the total distance = 90 miles and the total time = 7 hour 30 minutes = 7 hour + (30/60) hour = 7.5 hours. Hence:

Average speed = 90 / 7.5 = 12 miles/hour

Difference between the average speed = 60 miles/hour - 12 miles per hour = 48 miles/hour